Folding chair



May 15, 1934. J. D. WELLIVER FOLDING CHAIR Filed Feb. 6, 1933 Patented May 15, 1934 UNITED STATES PATENT "OFFICE FOLDING CHAIR Jacob D. Welliver, Tacoma, Wash.

Application February 6, 1933, Serial No. 655,484

5 Claims. (01. 155-444) This invention relates to foldingchairs and has forits objects to provide a chair which, though folding, is perfectly rigid when extended and cannot accidentally fold up when in use; which folds into a very compact form thereby permitting it to be stacked into the'least possible space; in which the frames are made of straight parts; in which its back is shaped to form a comfortable curved support for the back of the user; which may be handled with considerable roughness, when open, without folding up; and which is light to handle and ship, cheap to make, simple andeasy to fold or unfold, and comfortable in use;

I attain these and other objects by the devices, mechanisms, and arrangements illustrated in the accompanying drawing, in which Fig. 1 is a rear view of the chair when folded; Fig. 2 is a front view thereof;

Fig. 3 is a vertical section thereof, takenon the line 33 in Fig. 2;

Fig. 4 is a side view of the chair being opened;

Fig. 5 is a similar view of it fully opened;

Fig. 6 is a front view of the upper part of the back board and its supporting rail;

Fig. '7 is a similar view of the back-bending bar;

Fig. 8 is a section on the line 88 in Fig. 3; and

Fig. 9 is an enlarged section of the back-bending board.

Similar numerals of reference refer to similar parts throughout the several views.

Referring to the drawing, it will be seen that my improved folding chair has a main, or outside, frame composed of the two straight side bars 1, rigidly connected together by the foot bar 2, the seat bar 3, and the back-bending bar 4. Also the said side bars 1 are connected by the top back rail 5 which is pivotally mounted between said side bars 1 by means of trunnions 6 (Fig. 6) lying in suitable sockets formed in the inner sides of the said side bars 1. When the seat is opened for use the side bars 1 extend from the back of the user downward at a forward angle to a point under the front part of the seat.

The supplemental frame is narrower and shorter than the main frame and is pivoted thereto. This supplemental frame comprises two straight side bars '7, each pivoted to the inner side of the main side bars 1, at a point above the central point of said side bars '7, by means of the pivot pins 8, and said bars 7 are rigidly secured together by means of the rear foot bar 9 and the pair of diagonally crossing bars 10. The upper ends of the side bars '7 are pivotally connected to the seat. The supplemental frame, when opened for use, extends from the front part of the seat backward at a downward angle to a point under the back part of the chair. The two frames together form the legs and support for the seat and back of the chair.

' The seat comprises a fiat board 11, preferably made of three-ply wood construction, having two seat beams 12 rigidly secured" thereto. These beams 12 are spaced to lie inside of the ends of the supplemental frame members 7'. The seat board 11' may be as wide as or even wider than the main frame but the rear portion is cutaway to permit it to pass freely between the side bars 1 of said main frame, as clearly shown in the upper part of Fig. 2. The front ends of the seat beams 12 are pivoted to the-upper ends of the side bars '7 of the supplemental frame'by means of pivot pins 13. The seat beams 12 are also connected to the side bars 1 of the mainframe by a means of two metal straps 14 (Figs. 1, 4 and 5 The metal straps 14 arepivoted to the seat beams 12 by the pivots 15 andto the main frame members 1 by the pivots 16. The distances between v the respective pivots 8 and 13, 13 and 15, 8 and 16, and 16 and 15, are such that when the seat is folded (Fig. 3) the said lines coincide and the seat board 11 lies flat against the front edges (Fig. 5) the lines between the pins 8 and 13, and 8 and 16 are such as to cause the seat board 11 to tip upward slightly in front, and the lines between the pins 13 and 15, and 15 and 16 coincide. The two seat beams 12 are notched at 17 (Fig. 4) v of the side bars 1, while when the seat is opened to fit over the upper edge of the seat bar 3 of the 9}) main frame (Fig. 5) when the seat is fully opened for use. The length of the seat board 11 is such as to extend well back of the frame 1 when the chair is fully opened.

The back of my improved folding chair is composed of the above-described back rail 5, which is pivotally mounted between the bars 1 and which is free to turn therebetween, to which is rigidly secured a back board 18. This back board 18 is slightly narrower than the space between the seat beams 12, between which it lies when folded (Fig. 8), and is long enough to reach below the level of the seat board 11 when the chair is opened. The back board 18 is preferably made of three-ply wood construction, about onequarter of an inch in thickness, which is'thin enough to have the required flexibility and yet is very strong. The above-mentioned backbending bar 4 is firmly secured to the rear side of the two side bars 1 of the main frame at a point about one-third of the distance between the top rail 5 and the seat bar 3. The central portion of this bar 4, in line with the width of the back board 18, is shaped substantially as shown in Figs. '7, 8 and. 9 that is to say, it has a forward-extending enlargement 19 on its front face, said enlargement being thickest alongthe upper edge and extending down with a curved surface and diminishing in thickness to the lower edge (Fig. 9). This shape corresponds with the fiexure of the back-board, as hereinafter described. When the chair is being opened the rear edge of the seat board 11 engages the front face of the back board 18 and forces it backward against the back-bending bar 4. As the seat is forced fully down, it bends said back board 18.

as clearly shown in Fig. 5. If the top rail 5 were rigidly attached to the bars 1, the back board 18 would be soon torn therefrom under the bending strain imposed thereon. Also if the bending bar 4 were not shaped so as to follow the curvature of the fiexure of said back board 18, and thusto engage a large surface of the board 18, the said board 18 would break at or near the said bending board 4. By providing the pivoted rail 5 and the shaped bulge 19 of the bar 4 I am able to make the back of the chair of wood and thereby keep the weight of the chair as low as possible and yet provide a comfortable back to the chair. The strain of the back board 18 causes a heavy pressure on the rear edge of the seat board 11 and, since this pressureis directed above the pivots 15 and 16, it prevents the said board llfrom slipping up accidentally to fold the chair; indeed, the friction between the edge of the seat board 11 and the front side of the back board 18 issufficient to hold the board 11 down inopen position.

. 7 When it is desired to fold thechair, the rear portion of the seat board 11 is forcibly pulled upward until it releases the back board 18 from pressure, and then the parts quickly and easily move into their folded positions.

Having described my invention, what I claim and desire to secure by Letters Patent, is

1. A folding chair comprising a main and a supplemental frame, pivoted together to cross each other; a seat pivoted at its front edge to the upper end of said supplemental frame; a pair of metal straps connecting said seat with said main frame; a flexible back board, supported at its upper end by the upper end of said main frame and passing downward therefrom; and means on the main frame to restrain rearward movement of the back board, the lower end of said back board being adapted to be engaged by the end of said seat, when opened, and to be flexed rearwardly thereby.

2. A folding chair as set forth in claim 1, wherein said back board is secured to the top rail of said main frame, and wherein said top rail is pivotally secured across the main frame.

3. A folding chair as set forth in claim 1, wherein said main frame is provided with a backbending bar below the top of the back board against which said back board is pressed by the end of said seat to flex said back board.

4. A folding chair as set forth in claim 1, wherein said main frame is provided with a back-bending bar below the top of the back board shaped to conform with the flexure of the back board, against which said back board is pressed by the end of said seat to flex said back board.

5. A folding chair as set forth in claim 1, wherein said main frame is provided with a backbending bar below the top of the back board shaped to conform with the flexure of the back board, against which said back board is pressed by the end of said seat to flex said backboard, and wherein said back board is supported by a top rail, said top rail being pivotally secured across 

